Generally, a water supply valve, which is configured to control the temperature and flow rate of water when supplying water, means a water control valve that controls the flow rate of water supplied from an outside water source (including hot water supplied from a boiler) and controls the temperature of water by selecting cold water or hot water, or by mixing cold water and hot water.
The water supply valve capable of controlling the temperature and flow rate of water may be installed in a kitchen, at an appropriate position above a sink, or in a bathroom (including a public bath), at a predetermined position so that a user can easily use water by manipulating the valve as desired.
Conventional water supply valves to control the temperature and flow rate of water when supplying water have been classified into knob-operated valves, which can control the flow rate and temperature of water by manipulating rotary knobs to select cold water or hot water or to mix the cold water and hot water, and lever-operated valves, which can control the flow rate of water by moving a lever upwards or downwards and control the temperature of water by rotating the lever leftwards or rightwards to select cold water, hot water, or a mix of the cold water and hot water.
Described in detail, in conventional knob-operated water supply valves, a cold water knob, which is manipulated to discharge cold water at a controlled flow rate, and a hot water knob, which is manipulated to discharge hot water at a controlled flow rate, are provided on opposite sides of a valve body. Thus, when it is desired to use cold water or hot water exclusively, a user can easily control the flow rate of water by manipulating a knob designated for cold water or hot water. However, when it is desired to use mixed water of a desired temperature (between the temperature of hot water and the temperature of cold water), the two knobs (for cold water and hot water) must be carefully manipulated to provide the desired temperature so that the knobs trouble users while manipulating the knobs and the knob-operated valves are inconvenient to the users.
Particularly, the conventional knob-operated valves each have a plurality of valve cartridges used for separately controlling the flow rates of cold water and hot water. Thus, the valve cartridges of each of the conventional knob-operated valves comprise many elements, complicating the construction of the water supply valves.
In an effort to overcome the above-mentioned problems, in recent years, a water supply valve which has a structure to control the flow rate and temperature of water at a predetermined position therein has been proposed and used. However, this water supply valve causes a structural problem in which the valve may change the existing temperature of water during flow rate control operation and change the existing flow rate of water during temperature control operation. Thus, this water supply valve may unnecessarily waste water and may start operation of a boiler to heat water, and un-desirably consume excessive energy.